請問這個句子為什麽E答案不對

語法題,替換有底線的部分,我認為E不是很平行的並列結構嗎?為什麽答案是D?不理解

7. The most common reasons for an employee's unwillingness to accept a transfer are that mortgage rates are high, housing in the new location costs more, and the difficulty of selling the old home.

(D) high mortgage rates, the greater cost of housing in the new location, and it is difficult to sell the old home
(E) high mortgage rates, the greater cost of housing in the new location, and the difficulty of selling the old home